package main

import (
	"fmt"
	"log"
	"math/big"
	"net/http"
	"os"

	"4vif5i.gitea.cloud/numenor-labs/discourse/poc/backend/feedback"
	"github.com/ethereum/go-ethereum/accounts/abi/bind"
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/crypto"
	"github.com/ethereum/go-ethereum/ethclient"
	"github.com/gin-gonic/gin"
)

var (
	rpcURL          = os.Getenv("RPC_URL")
	contractAddress = os.Getenv("CONTRACT_ADDRESS")
	privateKey      = os.Getenv("PRIVATE_KEY")
)

func main() {
	// Connect to Sepolia
	client, err := ethclient.Dial(rpcURL)
	if err != nil {
		log.Fatalf("Failed to connect to Ethereum client: %v", err)
	}

	// Set up HTTP server
	router := gin.Default()
	router.OPTIONS(
		"/submit-feedback", func(c *gin.Context) {
			c.Header("Access-Control-Allow-Origin", "*")
			c.Header("Access-Control-Allow-Methods", "POST, OPTIONS")
			c.Header("Access-Control-Allow-Headers", "Content-Type")
			c.Status(http.StatusOK)
		},
	)
	router.POST(
		"/submit-feedback", func(c *gin.Context) {
			c.Header("Access-Control-Allow-Origin", "*")
			c.Header("Access-Control-Allow-Methods", "POST, OPTIONS")
			c.Header("Access-Control-Allow-Headers", "Content-Type")
			var request struct {
				Proof    string `json:"proof"`
				Feedback string `json:"feedback"`
			}
			if err := c.BindJSON(&request); err != nil {
				c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request"})
				return
			}

			// Mocked ZKP verification
			if request.Proof != "valid_proof" {
				c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid proof"})
				return
			}

			privateKeyECDSA, err := crypto.HexToECDSA(privateKey)
			if err != nil {
				fmt.Println("Failed to parse private key:", err)
				c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to parse private key"})
				return
			}

			// Create the transactor (chain ID 11155111 is for Sepolia testnet, adjust as needed)
			auth, err := bind.NewKeyedTransactorWithChainID(privateKeyECDSA, big.NewInt(11155111))
			if err != nil {
				log.Fatalf("Failed to create transactor: %v", err)
			}

			// Instantiate the contract
			contract, err := feedback.NewFeedback(common.HexToAddress(contractAddress), client)
			if err != nil {
				fmt.Println("Failed to instantiate contract:", err)
				c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to instantiate contract"})
				return
			}

			// Submit feedback to blockchain
			tx, err := contract.SubmitFeedback(auth, request.Feedback)
			if err != nil {
				fmt.Println("Failed to submit feedback:", err)
				c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to submit feedback"})
				return
			}

			fmt.Println("Submitted feedback:", tx.Hash().Hex())
			c.JSON(http.StatusOK, gin.H{"transaction": tx.Hash().Hex()})
		},
	)

	log.Println("Server running on :3000")
	router.Run(":3000")
}